Sumitomo Electric Industries, Limited

Goro Sasaki

Hiroshi Yano

Sosaku Sawada

Kentaro Doguchi

Takashi Kato

Manabu Shiozaki

Atsushi Miki

Hideki Hayashi

Toshio Takagi

Hiroyuki Nakaya

Hiroyuki Yabe

Jiro Shinkai

Yoko Watanabe

Kazuhiro Tanida

Atsushi Hamakawa

The present invention provides a multimode semiconductor laser module. The module comprises a multimode laser element, an optical filter, a light-receiving elementand a temperature regulator. Multimode light from the laser elementis transmitted through the filterand then detected by the light-receiving element. The output of the light-receiving elementchanges according to the degree of overlap between the oscillation wavelength spectrum of the laser elementand the transmission wavelength region of the filter. The temperature regulatormodifies the oscillation wavelength region toward the desired region in response to the output of the light-receiving element. As a result, the oscillation wavelength region is stabilized.

Multimode semiconductor laser module, wavelength detector, wavelength stabilizer, and Raman amplifier

A multimode light generating module comprises an optical cavity and a light-receiving element. The optical cavity is constituted by a semiconductor optical amplification element, and an optical fiber having a grating. The optical fiber comprises a grating having an apodized periodic refractive index distribution, and the slope of the reflection spectrum in a longer wavelength region with respect to the peak wavelength &#x3bb;is gentler than that in the shorter wavelength region therewith. The grating satisfies the relationship of 0.5 nm&#x3e;&#x3bb;&#x2212;&#x3bb;&#x3e;0.1 nm. Here, &#x3bb;is defined by &#x3bb;-&#x3bb;, where &#x3bb;is the longer one of two wavelengths exhibiting a relative reflectivity of 0.2 with respect to the maximum reflectivity, and &#x3bb;is the shorter one of two wavelengths exhibiting a relative reflectivity of 0.2 with respect to the maximum reflectivity.

Multimode light generating module, semiconductor laser apparatus, and optical fiber amplifier

A main portion of an optical module includes a thermoelectric cooler and a chip carrier placed on the cooler A semiconductor light-emitting device a lens photodetectors , and an etalon are directly or indirectly mounted on the chip carrier . Supporting members and are also fixed on the chip carrier . A roof is supported by the supporting members and positioned above the etalon The roof supporting members and chip carrier are maintained at substantially equal temperatures by the cooler As a result, the temperature of the etalon is stabilized, and therefore the variation in the lock wavelength is suppressed.

Optical module and optical device

A fiber grating laser module comprises a semiconductor optical amplifier and a grating fiber in which a Bragg grating is formed in the core. The semiconductor optical amplifier provides a wave guide in which the light is generated and amplified by the carrier injection, the light emitting facet and the light reflecting facet. The Bragg grating in the grating fiber and the light reflecting facet of the semiconductor amplifier forms an optical resonator. The subject of the invention is that the reflectance of the Bragg grating at the Bragg diffraction wavelength is greater than 60%.

Semiconductor light emitting module

A semiconductor laser module includes a semiconductor laser having an active region between a light-reflecting surface and a light-exit surface thereof, and an optical fiber optically coupled to the semiconductor laser and including an optical fiber diffraction grating. The optical fiber diffraction grating selectively reflects light within a predetermined wavelength band. The wavelength band has a width larger than a wavelength interval of a longitudinal mode of light resonating between the light-reflecting surface and the light-exit surface.

Semiconductor laser module and optical fiber amplifier

In an optical link apparatus of the present invention, a hybrid IC which is a main amplifier of a receiver circuit, and a hybrid IC which is a transmitter circuit are mounted on an island of a lead frame. An OEIC in which electronic devices and a light receiving device which constitute a preamplifier of the receiver circuit are integrated is housed in a light receiving device unit. A light emitting device is housed in a light emitting device unit. Sleeves which are optical link components are installed at the light receiving device unit and the light emitting device unit, and one ends of the sleeves are protruded from a plastic molding to the outside. As wires are connected to lead pins, the hybrid ICs are electrically connected with the light receiving device unit and the light emitting device unit. The lead pins, the hybrid ICs, the light receiving device unit, the light emitting device unit, and the sleeves are integrally sealed by a plastic molding which is superior in productivity and processability. Therefore, the optical link apparatus which is small and superior in productivity can be achieved.

Optical link apparatus

In an opto-electronic integrated circuit of the present invention, in a first surface region of a semiconductor substrate, a pin-type photodiode is constituted on the basis of a photodiode layer formed on a first transistor layer. In a second surface region of the semiconductor substrate, a heterojunction bipolar transistor is constituted on the basis of only a second transistor layer separated form the first transistor layer. Since a plurality of heterojunction bipolar transistors are normally integrated for one pin-type photodiode, the thickness of the heterojunction bipolar transistors larger in number than the pin-type photodiode is set regardless of the thickness of the pin-type photodiode. The thickness of a high-resistance layer in the pin-type photodiode is set with an increased degree of freedom. When the first surface region of the semiconductor substrate is the inner region of a recessed step portion, and the second surface region of the semiconductor substrate is the outer region of the recessed step portion, a difference in thickness between the heterojunction bipolar transistor and the pin-type photodiode is absorbed by the depth of the recessed step portion. For this reason, the pin-type photodiode and the heterojunction bipolar transistor are formed to have almost the same surface level.

Opto-electronic integrated circuit

An opto-electronic integrated circuit is arranged to comprise a photodetector and a tunnel emitter bipolar transistor for first-stage amplification of a current generated in the photodetector, as formed on a substrate. The tunnel emitter bipolar transistor can be operated at high speed and has a high amplification factor, so that noise due to the base current can be reduced upon amplification of the current generated in the photodetector by light detection.

A light receiving module and its manufacturing method of an excellent structure which can make a good and uniform optical couple between an optical fiber and a light receiving element, and can improve its productivity. The light receiving module comprises a semiconductor substrate, a light receiving element mounted on a surface of the semiconductor substrate, a groove formed on a back surface of the semiconductor substrate, an inclined face in the back surface side facing the light receiving element, and an optical fiber fixed in the groove. A transmitted light signal through the fiber is reflected by the inclined face. The inclined face is formed at a distal end of the optical fiber, at the closed end wall of the groove, or a side wall of a dimple arranged on the extension line of the groove. The reflected light is admitted to a light receiving face of the light receiving element, from the back surface side of the semiconductor substrate.

Method of manufacturing a light receiving module with optical fiber

A photodetector of the present invention is devised to reduce the dark current by employing a novel guard ring structure suitable for a mesa type photodiode (PD). Namely, the PD of the present invention has the structure in which a p-type or n-type semiconductor region which is to be a light receiving area is surrounded by a semiconductor region (guard ring) of the same conduction type. A guard ring electrode is formed on the guard ring region and is kept at the same potential as an electrode on a region desired to reduce the dark current. Also, an opto-electronic integrated circuit of the present invention has such a structure that a PD, which is the photodetector of the present invention, and a circuit element such as a transistor are formed on a common semiconductor substrate and that an anode electrode or a cathode electrode of the PD is conductively connected to a gate electrode of a field-effect transistor or to a base electrode of a bipolar transistor.

Photodetector and opto-electronic integrated circuit

There is disclosed on optoelectronic integrated circuit comprising, a plurality of channels each including an optical receiving device for converting a received optical signal to an electric signal, and an amplifier for amplifying an output signal of the optical receiving device, the channels being integrated on the same semiconductor substrate, electric power source nodes of at least two of the amplifiers of the respective channels being connected to a common electric power source node, and the common electric power source node being connected through a resistor element to an electric source power supply terminal for supplying an electric source power to the channels.

Optoelectronic integrated circuit device

Photodetector and opto-electronic integrated circuit with guard ring

Light receiving module with optical fiber coupling

There is disclosed a photo-electronic integrated circuit device comprising a first and second output terminals for supplying first and second output signal of opposite polarities to an external differential input logic circuit, a photo-detecting device for converting an input light signal to an electrical signal, a first amplifier for amplifying the electrical signal of the photo-detecting device and outputting the same from the first output terminal as the first output signal, and a second amplifier for amplifying the output of the first amplifier and outputting the second output signal having the opposite phase to that of the first output signal, from the second output terminal.

Photo-electric integrated circuit device with opposite phase amplifiers

Present invention is to provide a process for producing an opto-electronic integrated circuit comprising a field effect transistor as an electronic device and a photo-diode as an optical device both formed on an InP substrate,

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Yokohama, Japan

Goro Sasaki